221444161 has 9 divisors (see below), whose sum is σ = 231849121. Its totient is φ = 211488772.

The previous prime is 221444143. The next prime is 221444173. The reversal of 221444161 is 161444122.

The square root of 221444161 is 14881.

It is a perfect power (a square), and thus also a powerful number.

It is not a de Polignac number, because 221444161 - 2⁷ = 221444033 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221444131) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 341940 + ... + 342586.

Almost surely, 2^221444161 is an apocalyptic number.

221444161 is the 14881-st square number.

221444161 is the 7441-st centered octagonal number.

It is an amenable number.

221444161 is a deficient number, since it is larger than the sum of its proper divisors (10404960).

221444161 is an frugal number, since it uses more digits than its factorization.

221444161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1340 (or 670 counting only the distinct ones).

The product of its digits is 1536, while the sum is 25.

The cubic root of 221444161 is about 604.9991220988. Note that the first 3 decimals are identical.

Multiplying 221444161 by its sum of digits (25), we get a square (5536104025 = 74405²).

Adding to 221444161 its reverse (161444122), we get a palindrome (382888283).

The spelling of 221444161 in words is "two hundred twenty-one million, four hundred forty-four thousand, one hundred sixty-one".